... occursin 6-8% of lung metastases [3]. 80% of them are fromadenocarcinomas. The common sites of primary fromwhich PLC occurs are can cers of breast, bronchus, and stomach [4,5]. The other described ... arecancers from colon, pancre as, kidney, cervix, thyroid,larynx and hypopharynx [6-8]. The cancers o f head and neck rarely show this type of metastasis. The exact reason is unknown. The describedsites ... manuscript and the literature search, GM reviewed andedited the manuscript, ST corrected and revised the manuscript, SS:reviewed the manuscript. All authors read and approved the finalmanuscript.Competing...